“I literally had written an opening which started with that sequence, and so it was quite literal, who was dead,” Mangold said. “But the reason we didn’t do it wasn’t to spare other films, it was that it redefined the movie. It made the movie about the X-Men, instead of being about Logan and Charles. And irrevocably, when you read the script opening that way, it became about this other tragedy, as opposed to that tragedy being something hovering like a shadow in the background for these characters.”

In the final film, Xavier’s mutant massacre happens off screen before the movie begins, although there is a news report that links the character’s deadly telepathic seizure at the casino hotel to a similar event that took place in Westchester, New York – the location of the X-Mansion — and the audience is left to imagine exactly who among the X-Men had been caught in the crossfire.